See how your 401(k) grows over time with employer matching, contribution rates, and compound investment returns.
| Age | Your Contribution | Employer Match | Investment Gains | Year-End Balance |
|---|
Enter your current age, planned retirement age, and annual salary. Then input your contribution percentage — the amount of your paycheck you're putting into the 401(k) — along with your employer's match formula. For example, if your employer offers "50% match up to 6% of salary," enter 50% as the match percentage and 6% as the salary limit. Finally, add your existing 401(k) balance and your expected annual return.
The calculator shows your projected balance at retirement, broken down by your contributions, employer contributions, and investment growth. Adjust sliders in real time to see how saving more today — or starting earlier — dramatically changes your retirement outcome.
The core formula for 401(k) compound growth is the future value of a growing annuity:
This illustrates why time is the single most powerful factor in 401(k) growth. Starting just 5 years earlier can nearly double your final balance.
The IRS sets annual limits on how much you can contribute to a 401(k):
Tip: If you are not yet maxing out the standard limit, focus on at least contributing enough to get your full employer match first — that's an immediate 50–100% return on your investment.
For 2025, you can contribute up to $23,500 per year to your 401(k). If you are age 50 or older, you can add a $7,500 catch-up contribution for a total of $31,000. Employees aged 60–63 have a new special catch-up amount of $11,250. These limits apply to employee contributions only — your employer's match is on top of these limits up to the overall $70,000 cap.
Employer matching is when your company contributes to your 401(k) based on what you put in. The most common formula is "50% match up to 6% of salary." This means if you earn $75,000 and contribute 6% ($4,500), your employer adds $2,250. You must contribute at least to the match ceiling to capture the full benefit — it's the best guaranteed return available.
You have four options when leaving a job: (1) roll over to your new employer's 401(k), (2) roll over to an IRA for more investment options, (3) leave it in your old employer's plan if they allow it, or (4) cash it out — which is generally the worst choice because you'll owe income taxes plus a 10% early withdrawal penalty if you're under 59½.
Traditional 401(k) contributions are pre-tax — you reduce your taxable income now but pay taxes on withdrawals in retirement. Roth 401(k) contributions are after-tax — no deduction today, but all qualified withdrawals are tax-free. If you're in a lower tax bracket now than you expect to be in retirement, the Roth generally wins. If you're in a high bracket now and expect a lower income in retirement, traditional is usually better.